Miniature watering devices, whether being provided in the form dripper, nozzle, sprayer or others, are widely used for controlling water flowing rate of water to gardens or garden plants. Thus, many kinds of miniature watering devices are provided with a specified mechanism able to adjust various degree of cross-area being available for water flowing, so that the flow rate of water can be controlled.
However, for the most miniature watering devices manufactured in prior art, a number of problems had been presented for many years. One obvious problem as known by people is that the water flow passageways may be blocked and clogged due to the reason that the grit or other foreign particles are accumulated within the water flow passageways. Another problem is when the water passageways within the miniature watering device, the grit or other foreign particles are not easy to be clean. Moreover, a further problem is individual units cannot accurately adjust the rate of water flow step by step.